NEW YORK -- One evaluator not paid by Boston offered this take on Mookie Betts, who will make his major league debut tonight, when the Red Sox try to take their three-game series against the Yankees on "Sunday Night Baseball" (8 p.m. ET, ESPN and WatchESPN):

“Tremendous feel for the strike zone,” the evaluator wrote. “Handles bat and is not a slap type. There is strength in the swing. Strong running ability. Defense really strong at second base. Limited time in center field, but early indications are that he is really solid.”

Another evaluator said: “He belongs in the major leagues. He’s a good player.”

Betts has almost as many extra-base hits (88) as strikeouts (90) over the past season and a half in the minors, with 132 walks and 67 stolen bases. He is 21 years old and slender and does not hit a lot of homers, yet. But his promotion, and the entrenchment of Brock Holt as an every-day player, seems to signal a change in direction for the Red Sox front office, a shift in lineup building. This is the Summer of the Improv.

Boston has an incredible history of power hitting, from Ted Williams to Carl Yastrzemski to Jim Rice to the 3-4 combination of David Ortiz and Manny Ramirez. In the midst of the 1977 season, the Red Sox slammed homers in 33 consecutive games. Home runs have always been the foundation of the Red Sox offense, including in 2013, when Boston clubbed 178 homers -- sixth-most in the majors -- on the way to winning the World Series.

But it just hasn’t happened; Boston is 24th in home runs, with 61, and incredibly, the Red Sox are 27th in runs. They have looked around for power hitters in the trade market, just like a lot of other teams, and have identified few options.

So now Boston is changing. Instead of waiting for bigger, slower hitters to start mashing homers, the working philosophy now seems to be: If you hit -- no matter how you hit -- you are going to play.

Holt opened the season in the minor leagues, and now he is Boston’s leadoff man, hitting .321. Along comes Betts, who could play right field or center, depending on the needs of the day. Pierzynski probably needs to show something soon or else he will be the next to go, to be replaced by Christian Vazquez, a strong defensive catcher who also doesn’t hit for a lot of power; he has three home runs in Triple-A this season, along with a .325 on-base percentage.

It’s possible that by the time Aug. 1 rolls around, the bulk of the Boston lineup might look like this:

The rest of the lineup will be determined by who hits. Daniel Nava has improved his batting average from .130 to .216 since he was promoted; if he hits, he will play. Stephen Drew has one hit in 32 at-bats and quite simply looks terrible at the plate, completely off-balance. Bogaerts was moved from shortstop to third base and stopped hitting, but he will probably continue to play while he continues to develop.

The player who probably has the most to lose with the promotion of Betts is Jackie Bradley Jr., who knows Betts better than anyone, having roomed with him in instructional ball in the fall of 2011. Bradley’s defense has been exceptional, but at some point, the Red Sox will need better production from his spot; he is hitting .206 with a staggering 76 strikeouts and just 23 walks. The Red Sox could play Holt in center and Betts in right field, which is incredible, given that both were regarded as infielders just a month ago.

Whatever alignment evolves for the Red Sox, they won’t hit a lot of homers. But they should be pretty good defensively, they should put the ball in play more, and they will be more athletic, with almost half of their every-day lineup made up of players either in their first or second season.

They have waited for the old guard to hit, and it didn’t happen. Now the Red Sox will go with what they hope is basically a lineup of badgers -- not big, not powerful, but aggressive and relentless -- during a season in which the American League East is more mediocre than it has been in years and is there for the taking.